xref: /original-bsd/lib/libc/vax/gen/frexp.s (revision 7323bcb8)
1/*
2 * Copyright (c) 1980 Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms are permitted
6 * provided that the above copyright notice and this paragraph are
7 * duplicated in all such forms and that any documentation,
8 * advertising materials, and other materials related to such
9 * distribution and use acknowledge that the software was developed
10 * by the University of California, Berkeley.  The name of the
11 * University may not be used to endorse or promote products derived
12 * from this software without specific prior written permission.
13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16 */
17
18#if defined(LIBC_SCCS) && !defined(lint)
19	.asciz "@(#)frexp.s	5.5 (Berkeley) 06/27/88"
20#endif /* LIBC_SCCS and not lint */
21
22/* C library -- frexp(value, eptr) */
23
24#include "DEFS.h"
25
26ENTRY(frexp, 0)
27	movd	4(ap),r0		# (r0,r1) := value
28	extzv	$7,$8,r0,*12(ap)	# Fetch exponent
29	jeql	1f			# If exponent zero, we're done
30	subl2	$128,*12(ap)		# Bias the exponent appropriately
31	insv	$128,$7,$8,r0		# Force result exponent to biased 0
321:
33	ret
34